Researchers seek to improve drug delivery with hydrogels

November 2, 2012

Researchers in Japan have developed a technique which allows them to control and target drug delivery to specific sites of the body at specific times, thus reducing side effects and improving treatment dramatically. The results were published recently in the journal Science and Technology of Advanced Materials.

Better control over the delivery of drugs to specific sites in the body at specific times would reduce unwanted side effects and improve medical treatment dramatically. 'Smart' polymers are promising materials for controlling drug delivery, since they change their properties in response to specific stimuli. However, they usually require continuous stimulation to maintain these changes. Now, researchers led by Takao Aoyagi at the MANA, National Institute for Materials Science, Japan, have developed an approach that could allow more subtle control and timing of drug delivery.

The new technique uses hydrogels, which are a type of 'smart' polymer made of water-soluble long-chain molecules. The team first showed that they could control the acidity inside a hydrogel by loading it with a compound called o-NBA. This releases protons, which increases acidity, when irradiated with UV light. When o-NBA-loaded hydrogel was irradiated, acidity increased inside; if only part of the gel was irradiated, acidity throughout increased gradually as protons diffused.

Aoyagi and his colleagues then loaded hydrogel with o-NBA and L-DOPA, a precursor of the brain chemical dopamine that is used in the treatment of Parkinson's disease. The change of acidity in the gel upon UV irradiation caused L-DOPA to be released because the acidity disrupted the interaction of L-DOPA with the molecules in the gel.

Irradiation with UV not only enhanced overall L-DOPA release from the hydrogel, but also caused an extra 'explosive' release five hours after irradiation. This allowed the drug release to be timed, as well as triggered, in a controlled way.

Being able to control the release of drugs from hydrogels by triggering a change in acidity could help to design programmable drug delivery techniques that offer improved targeting of treatment.

Related Stories

(Phys.org) -- For people suffering from diabetes and other hormonal disorders, staying healthy means staying vigilant; effective treatment requires periodic and precise doses of drugs throughout the day.

People have been combining materials to bring forth the best properties of both ever since copper and tin were merged to start the Bronze Age. In the latest successful merger, researchers at the National Institute of Standards ...

People with Parkinson's disease commonly suffer a slowing or freezing of movement caused by the death of neurons that make dopamine, a key chemical that allows brain cells to send and receive messages essential to voluntary ...

Scientists are reporting development and successful initial testing of the first practical "smart" material that may supply the missing link in efforts to use in medicine a form of light that can penetrate four inches into ...

A new technology which delivers sustained release of therapeutics for up to six months could be used in conditions which require routine injections, including diabetes, certain forms of cancer and potentially HIV/AIDS.

University of California, San Diego bioengineers have developed a self-healing hydrogel that binds in seconds, as easily as Velcro, and forms a bond strong enough to withstand repeated stretching. The material has numerous ...

Researchers in AMBER, the Science Foundation Ireland-funded materials science research centre, hosted in Trinity College Dublin, have used the wonder material graphene to make the novelty children's material silly putty (polysilicone) ...

(Phys.org)—For the first time, researchers have simulated particles that can spontaneously self-assemble into networks that form geometrical arrangements called Archimedean tilings. The key to realizing these structures ...

Scientists at The University of Manchester and Karlsruhe Institute of Technology have demonstrated a method to chemically modify small regions of graphene with high precision, leading to extreme miniaturisation of chemical ...

Machine learning, a field focused on training computers to recognize patterns in data and make new predictions, is helping doctors more accurately diagnose diseases and stock analysts forecast the rise and fall of financial ...

The next time you place your coffee order, imagine slapping onto your to-go cup a sticker that acts as an electronic decal, letting you know the precise temperature of your triple-venti no-foam latte. Someday, the high-tech ...

0 comments

Please sign in to add a comment.
Registration is free, and takes less than a minute.
Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.